Repository Dispatch - Polling for Run

One of the biggest features lacking in the GitHub Actions space today is centered around repository_dispatch events. When a repository_dispatch is triggered via an API call, the response does not contain any return information, meaning that you as a developer have no way to know information including the success/failure/completion-time of the called workflow. You could consider just getting all of the recent runs triggered, but you're very much in a race condition world!

Thanks to a newer feature GitHub Actions recently released, there is a viable workaround to this, although it's not pretty. What unlocks this possibility is somewhat obscure, and that's Dynamic names for workflow runs. Here's how Dynamic names help us solve our problem:

• Caller workflow generates some unique name, such as a UUID
• Caller workflow passes the UUID to the called workflow via it's client_payload data when triggering the repository_dispatch
• Called workflow uses the syntax run-name: ${{ github.event.client_payload.id }}, which dynamically names the workflow the UUID value.
• Caller, after triggering the repository_dispatch, now can poll the workflow runs to find one who's name is the UUID!
• Caller, once the workflow with the UUID is found, can either poll or use the GitHub CLI gh run watch to watch that run for it's completion results.

Example

Working code for this section:

• Triggering a repository_dispatch and polling
• Listening for a repository_dispatch using a dynamic name
• Polling script

In the case of the example above, you can see a workflow get generated with a random ID: